Improvement in fire-proof safes



' m9. SAFES, BANK Pmmlon AND RELATED nEvlcE-s.

ANL PHOT0-LI1HD. C0. N.Y. (OSBURNE'S PROCESS) WILLIAM II. BUTLER,

or Nnw YORK, N. Y.

IMPROVEMENT IN FIRE-PROOFISAFES.

Specification forming part of Letters Patent No. 65,055, dated May 28, 1867.

To all whom it may concern:

Be it known that I, WILLIAM H. BUTLER,

of the city and county of New York, and State of New York, have invented certain new and useful Improvements in Safes and Analogous Burglar-Proof Structures, and I do `hereby declare that the following is a full and exact description thereof. u AMy invention relates to the lmaterial of which the walls of the structure, the doors, &c., are made, and to the manner in which it is arranged and secured. The safe is intended to resist fracturey with as much force as any material before known, and to be more diflicult to drill or trephine.

I will rst proceed to describe what I consider the best mode or modes of carrying out my invention, and will afterward designate the points which I believe to be new. v

The accompanying drawings form part of this specification.

Figure l is a vertical section across a safe made according to my invention. The outlines s how the general form, which is intended to correspond with that of the safes ordinarily in use. One portion is represented in section, so as to indicate the material and arrangement of the parts; the remainder must be understood to be similarly made. Fig. 2 is a section through one thickness, showing the arrangement of the pieces of steel and iron which form the material on a larger scale. Fig. 3 shows the same, but with the pieces of steel and iron differently arranged. Fig. 4 is a diagram, indicating the condition when a drill strikes the hard material on side of the hole. Fig. 5 is a diagram, indicating the conf shelves, and all the approved appliances of whatever character.

The parts A, tinted blue, are good steel. They may be of cast-steel, shear-steel, Bessemer steel, or any of the other grades known which will become very hard when suddenly cooled, and without materially losing strength. B B, Src., are soft iron. They may be Low Moor, J uniata, (Pennsylvania,) charcoal-iron, or any other quality which is strong and soft, and which is easily and reliably welded to itself and to steel.

The pieces of iron and of steel are manufactured in short lengths, of uniform or about uniform thickness, and are piled up like brickwork, with the addition of boraX or other suitable iiux over the whole or the greater portion of their surfaces. These pieces being' piled together alternating, the iron and steel, as represented, are heated to the'weldingheat in a clean charcoal re, and are welded into a solid mass under a heavy trip-hammer or by being passed through the rolls of a proper rolling-mill. The result is a thick plate of metal which is in a condition to become very irregularly hardened throughout its mass when the whole is heated and plunged in water. I produce and countersink suitable rivet-.holes in these pieces by punching and by properly drifting or reaining holes to correspond exactly to each other. The whole or a great portion of this work may be done while the plates are at a high temperature, and the whole must be donc before the plates are hardened. When the holes are properly iinished, a cherry-red heat is taken on each plate, and it is plunged as rapidly as possible into cold water or other hardening preparation, the purpose being to render the steel in each plate as hard as possible. This operation is effected on the steel without inducing any material change in the hardness of the iron, provided the iron has been properly selected and properly treated. These plates are afterward riveted together, in the manner indicated in Fig. l.

No single rivet extends continuously through the wall, but each rivet joins only a portion of the plates, the object of this arrangement being to preclude the possibility of a burglar drilling through into the safe and introducing I gunpowder or the like through a hole in the line of the rivet.

`All the 'plates of the safe may be made of my improved material; or a portion may be of this, and a portion of common iron, or of homogeneous hardened steel. I have represented Fig. 1 as made With three plates, the outer and innermost of which are of my iinproved material, While the center plate is of common iron. When a burglar attempts to vdrill or trephine, his cutting instrument acts alternately on the soft iron and on the hardened steel. The effect of this great inequality in the hardness of the material is to break the drills and trephining tools 5 and although it is possible, by the exercise of great pressure, to drill through the best chilled iron, and even to make some Wayinto hardened steel 'when it is of uniform hardness, I believe it to be absolutely impracticable to drill or trephine through my improved material.

It is not absolutely necessary that the material be piled obliquely in uniform courses like brick-Work. Ihave shown this character v.of structure in Figs. 1 and 2, and a close any given plate thereof Without meeting them.

I have designated the rivets by which the several plates are preferably joined, asin Fig. 1, by the letter G, and the soft-iron interior-plate in my structure by the letter D. There is great increase in the strength and toughness of the safe or of the door by sand- Wiching together the softiron and the brick- Work iron in the manner therein represented.

I greatly prefer for most purposes making a safe or a door not entirely of my improved material, but partly of such material and partly of soft iron, joined by the means represented.

Having fully described my invention, What I claim as new therein, and desire to secure by Letters Patent, is-

1. v The tesselated Work or interspersed masses of steel united with a softer metal, B, by being rolled or forged together and afterward hardened by sudden cooling, so as toform a conglomerate metal of lunequal hardness, the masses'being arranged substantially as and for vthe purpose herein speciiied. .v

2. In burglar-proof structures composed of more than one layer of plates, employing plates composed of soft iron, joined with plates containing hardened steel by means of rivets C' or their equivalents, arranged relatively to each other and to the several plates, substantially in the mannerv and for the purpose herein set forth. l

W. H. BUTLER.

Witnesses:

W. G. DEY, EMIL VossNAcK. 

